|Publication number||US7392654 B1|
|Application number||US 11/117,912|
|Publication date||Jul 1, 2008|
|Filing date||Apr 29, 2005|
|Priority date||Feb 27, 2004|
|Also published as||US6973783, US7536857, US7900447, US8327639, US8443598, US8707692, US9050880|
|Publication number||11117912, 117912, US 7392654 B1, US 7392654B1, US-B1-7392654, US7392654 B1, US7392654B1|
|Inventors||Raymond Hauser, Lonnie E. Holder|
|Original Assignee||Hydro-Gear Limited Partnership|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (49), Non-Patent Citations (1), Referenced by (14), Classifications (18), Legal Events (3)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application is a continuation-in-part of U.S. patent Ser. No. 10/788,534, filed Feb. 27, 2004, U.S. Pat. No. 6,973,783, issued Dec. 13, 2005, which is incorporated herein by reference in its entirety.
This invention relates to hydraulic pump and motor assemblies.
A zero turn drive apparatus comprising dual tandem pumps and corresponding hydraulic motors is disclosed herein. The details of this invention are set forth below in connection with the detailed description of the embodiments.
The following is a description of multiple embodiments of this invention. Where appropriate, like numerals indicate identical or substantially identical components, and similar numerals with a different initial numeral indicate similar components with certain differences as specified. Further, in each of the embodiments discussed herein, identical numerals followed by “a” and “b” identify elements that are either identical or are mirror images of each other. Therefore, for convenience, the descriptions of elements with numerals followed by “a” may apply equally to elements with identical numerals followed by “b.” Application of reference numerals in the aforementioned manner should have an obvious meaning to those with skill in the art.
In this embodiment, two generally identical pumps 11 a and 11 b are disclosed within unitary housing 52; as noted above, pumps 11 a and 11 b need not be identical and substantial variations are possible to one or the other within the scope of this invention. Pumps 11 a and 11 b are shown as the rotating axial piston type, although other designs could be used with minor modifications within the scope of this invention. Only certain elements of pump 11 a and its related structure are described in detail herein, as the operation of such pumps is generally known in the art. The design of pumps 11 a and 11 b, housing 52 and related elements are similar to the disclosures in U.S. patent application Ser. Nos. 10/175,206 and 10/767,315 U.S. Pat. Nos. 6,705,840 and 7,056,101, both of which are commonly owned with this application, the terms of which are incorporated herein by reference.
Housing 52 includes two generally identical pump chambers or cavities 59 a and 59 b and a gear chamber or cavity 30 formed therebetween, thus providing an integral housing for pumps 11 a and 11 b. A case fluid passage 55 a is formed in housing 52 to connect pump chamber 59 a and gear chamber 30. Case fluid passage 55 b similarly connects pump chamber 59 b with gear chamber 30. Both fluid passages 55 a and 55 b permit hydraulic oil flow between pump chambers 59 a and 59 b and gear chamber 30. This arrangement permits the use of a single case drain (not shown) which can be formed anywhere in housing 52 to permit oil flow to a separate reservoir (not shown) mounted elsewhere on vehicle 115. If this case drain is in gear chamber 30, it will assist in preventing contamination of pumps 11 a and 11 b with debris from bevel gears 35 a, 35 b and 36, as well as assist in reduction of heat, as the warmer fluid from pumps 11 a and 11 b will be carried to the center of housing 52. A cover 53 is secured to the bottom of housing 52 to close gear chamber 30.
In each embodiment described herein, cavities 59 a, 59 b and 30 remain in fluid communication with one another. It will be appreciated by those in the art that pump chambers 59 a and 59 b and gear chamber 30 can be segregated from one another by housing 52. In such an embodiment, a plurality of case drains must be provided to remove oil from pump chambers 59 a and 59 b, respectively, and these separate case drains could be formed in a variety of locations.
Center sections 122 a and 122 b are mounted on opposite ends of housing 52 and act to seal pump chambers 59 a and 59 b, and may be secured thereto by screws 22 or other means. Center sections 122 a and 122 b could be referred to as porting plates, end caps or the like. As noted above, only center section 122 a will be described herein.
Preferably, motor 126 a is of the geroller type, but various other motor designs, such as axial piston motors and gear motors, may also be employed within the scope of this invention. Motors such as motor 126 a are also generally well known in the art and, therefore, it also is not described in detail. Motor 126 a is connected to center section 122 a by fasteners 130, which are typically screws, but other fastening means may also be used. Motor 126 a is connected to and drives output axle 128 a, which in turn is connected to an output device, such as wheel 138.
Pump 11 a on the left hand side of
Center section 122 a may be preferably composed of cast iron, although it could also be aluminum or other materials depending on the application needs. The use of running plate 37 a, also called a valve plate, to mount cylinder block 31 a will add additional strength and durability, particularly if center section 122 a is composed of aluminum. Cylinder block 31 a could also run directly on a surface formed on center section 122 a. Pump 11 a is of the cradle mounted swash plate design; as shown in
While trunnion arms 21 a and 21 b are shown extending out of housing 52 on the same side as and thus parallel to input shaft 54, it will be understood that trunnion arms 21 a and 21 b could be mounted on any side of housing 52, possibly requiring a corresponding change in the orientation of swash plates 32 a and 32 b, respectively, and also possibly requiring a change in the orientation of the porting in center sections 122 a and 122 b, respectively. Trunnion arms 21 a and 21 b need not be on the same side of housing 52. By way of example, if trunnion arm 21 a is rotated 180° from the orientation shown, housing 52 would need to be modified, but the orientation of porting in center section 122 a would not need to be changed. If, however, trunnion arm 21 a was rotated 90° from the orientation shown so that it was on an adjacent side of housing 52, the porting in center section 122 a would also need to be similarly rotated, along with the proper housing modifications. It will also be understood that other types of swash plates 32 a and 32 b, such as a trunnion mounted swash plate, could be used.
As will be obvious to one of ordinary skill in the art, optional elements, such as an oil cooler, external reservoir or expansion tank could easily be attached to pump and motor assembly 120. Various fittings and connections, such as housing or center section case drains and appropriate hydraulic lines, would be used to connect these elements to assembly 120 and to each other. These elements have been removed to simplify the drawings. Input shaft 54 extends into housing 52; as shown in
Bevel gear 36 is mounted on input shaft 54 inside gear chamber 30 and is drivingly engaged to a first driven bevel gear 35 a mounted on first pump shaft 63 a. Bevel gear 36 is likewise drivingly engaged to a second driven bevel gear 35 b which is similarly mounted on and driving second pump shaft 63 b. A benefit of this design is that pump shafts 63 a and 63 b can be sized appropriately for their respective pumps 11 a or 11 b; only input shaft 54 needs to be sized appropriately to handle the torque of both pumps 11 a and 11 b as well as the torque requirements of the auxiliary device attached to output pulley 58.
Pump shaft 63 a extends from gear chamber 30 into first pump chamber 59 a and is engaged to and drivingly rotates pump cylinder block 31 a. Bearing 44 a provides support within housing 52. Pump shaft 63 b also extends from gear chamber 30 into pump chamber 59 b where it engages and drivingly rotates pump cylinder block 31 b in a similar manner. As shown in, e.g.,
Pump shaft 63 a extends through center section 122 a into charge pump 124 a. Charge pump 124 a can be a gerotor or other style of charge pump, such as a vane pump, geroller, gear pump or any other known design. A charge pump for use in connection with a hydrostatic pump is shown, e.g., in commonly owned U.S. Pat. Nos. 5,555,727 and 5,628,189 the terms of which are incorporated herein by reference.
The location of input shaft 54 on the side of housing 52 permits the location of charge pumps 124 a and 124 b on opposite ends of housing 52. It is possible that only one of charge pumps 124 a or 124 b would be required, depending on the application for which apparatus 120 is to be used. Similarly, the output of one charge pump mounted on one center section could be attached by means of internal or external hoses or integral passages to provide charge pressure to the other pump associated with the other center section.
It will also be understood that these embodiments could include additional gear reduction. For example, in
Details of center section 122 a are shown in
Because pump 11 a, porting 41 a, porting 42 a, and motor 126 a form a closed loop, and because there may be a need to back drive motor 126 a, such as may occur if engine 116 becomes non-functional, a bypass valve 66 a may be provided. Bypass valve 66 a is typically positioned so that fluid flow in ports 41 a and 42 a is relatively unimpeded, for example, through annular areas 61 a and 62 a. When bypass valve 66 a is actuated, fluid is permitted to flow between ports 41 a and 42 a by way of passages 64 a formed in valve 66 a, so that motor 126 a is able to turn more freely.
Input shaft 168 does not extend through cover 153 in this embodiment and therefore cover 153 need not be additionally strengthened to support the torque loads from an output pulley, although this design could be modified to have such a pass through design as is shown in
In each of the previous embodiments, the center sections have each been depicted as being a one piece unit.
One advantage of this embodiment is that the distance, as shown as D1 in
Another embodiment of the present invention is shown in
For powering a mower deck 317, deck lift or other auxiliary device, a power take off assembly 170 may also be provided. As shown in
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangement disclosed is meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any equivalents thereof.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1539616||Jul 27, 1920||May 26, 1925||Waterbury Tool Co||Variable-speed gear|
|US2875701||Aug 30, 1954||Mar 3, 1959||Heinrich Ebert||Hydrostatic piston engine|
|US2914219||Apr 11, 1957||Nov 24, 1959||Chiantelassa Attilio||Apparatus for dispensing a mixture of two liquids in any continuously variable ratio|
|US3775981 *||Feb 1, 1972||Dec 4, 1973||H Molly||Hydrostatic drive unit|
|US3922931||Jan 4, 1974||Dec 2, 1975||Kubota Ltd||Speed change device for tractor transmissions|
|US4129192 *||May 17, 1977||Dec 12, 1978||Massey-Ferguson Services N.V.||Hydrostatic transmissions|
|US4252508||Mar 1, 1979||Feb 24, 1981||Linde Aktiengesselschaft||Pump unit|
|US4270480||Nov 14, 1978||Jun 2, 1981||The Secretary Of State For Industry In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland||Pinned suction anchors|
|US4534271||Jun 29, 1983||Aug 13, 1985||Linde Aktiengesellschaft||Dual machine aggregates with a connection for a consumer of mechanical energy|
|US4819508||Nov 18, 1987||Apr 11, 1989||Kanzaki Kokyukoki Mfg. Co., Ltd.||Transmission system for working vehicles|
|US4893524||Nov 15, 1988||Jan 16, 1990||Kanzaki Kokyukoki Mfg. Co. Ltd.||HST system axle driving apparatus|
|US4971535||Mar 3, 1989||Nov 20, 1990||Toyoda Koki Kabushiki Kaisha||Tandem rotary pump with pressure chamber between two intermediate side plates|
|US5040429||Dec 17, 1990||Aug 20, 1991||Del Castillo Richard A||Mechanical electric motor synchronizer|
|US5078222||Mar 2, 1989||Jan 7, 1992||Agri-Fab, Inc.||Zero turn transmission|
|US5207060||Sep 3, 1991||May 4, 1993||Sauer, Inc.||Tandem hydraulic motor|
|US5247794||Sep 11, 1990||Sep 28, 1993||Sundstrand Corporation||Cylinder block positive hold-down for cold start-up|
|US5304043||Oct 28, 1992||Apr 19, 1994||Avmed Compressor Corporation||Multiple axis rotary compressor|
|US5354180||Jul 9, 1993||Oct 11, 1994||Linde Aktiengesellschaft||Hydrostatic assembly having multiple pumps|
|US5501578||Feb 3, 1995||Mar 26, 1996||Sauer Inc.||Hydrostatic axial piston pump with three bearing arrangement|
|US5542307||Aug 10, 1994||Aug 6, 1996||Kanzaki Kokyukoki Mfg. Co., Ltd.||Hydrostatic transmission|
|US5800134||Nov 25, 1996||Sep 1, 1998||Kawasaki Jukogyo Kabushiki Kaisha||Tandem, swash plate pump having drive force take-out mechanism|
|US6022198||Aug 12, 1996||Feb 8, 2000||Brueninghaus Hydromatik Gmbh||Twin pump with a charging pump|
|US6199380||May 27, 1998||Mar 13, 2001||Kanzaki Kokyukoki Mfg. Co. Ltd.||Axle driving apparatus|
|US6301885||Feb 7, 2000||Oct 16, 2001||Tecumseh Products Company||Hydrostatic transmission having two-piece pump and motor block assembly|
|US6332393||Jul 16, 1999||Dec 25, 2001||Hydro-Gear Limited Partnership||Pump|
|US6361282||Jun 22, 1999||Mar 26, 2002||Brueninghaus Hydromatik Gmbh||Dual pump unit|
|US6363815||Apr 13, 1999||Apr 2, 2002||Kanzaki Kokyukoki Mfg. Co., Ltd.||Transmission mechanism of vehicle with HST|
|US6382339||Nov 12, 1999||May 7, 2002||Kanzaki Kokyukoki Mfg. Co., Ltd.||Driving apparatus for vehicles|
|US6425244||Aug 24, 2000||Jul 30, 2002||Kanzaki Kokyukoki Mfg. Co., Ltd.||Pump unit|
|US6474218||Aug 1, 2001||Nov 5, 2002||Honda Giken Kogyo Kabushiki Kaisha||Hydrostatic continuously variable transmission|
|US6487856||Oct 18, 2000||Dec 3, 2002||Kanzaki Kokyukoki Mfg. Co., Ltd.||Tandem pump unit|
|US6494686||Oct 30, 2000||Dec 17, 2002||Hydro-Gear Limited Partnership||Tandem pump and interface for same|
|US6672058||Mar 11, 2003||Jan 6, 2004||Hydro-Gear Limited Partnership||Zero turn transaxle|
|US6672843||Apr 8, 2002||Jan 6, 2004||Hydro-Gear Limited Partnership||Dual pump apparatus comprising dual drive shafts and auxiliary pump|
|US6705840||Jun 19, 2002||Mar 16, 2004||Hydro-Gear Limited Partnership||Inline tandem pump|
|US6736605||Oct 7, 2002||May 18, 2004||Kanzaki Kokyukoki Mfg. Co., Ltd.||Tandem pump unit|
|US6877302||Mar 3, 2003||Apr 12, 2005||Kubota Corporation||Mid-mount mower|
|US7147810 *||Oct 31, 2003||Dec 12, 2006||Fraunhofer Usa, Inc.||Drapable diamond thin films and method for the preparation thereof|
|US7162870 *||Mar 3, 2005||Jan 16, 2007||Hydro-Gear Limited Partnership||Pump assembly|
|US20030188909||Apr 1, 2003||Oct 9, 2003||Ryota Ohashi||Pump unit and working vehicle|
|US20040200657||Apr 10, 2003||Oct 14, 2004||Kerwyn Stoll||Hydraulic transmission for driving and steering wheels|
|US20040221573||Jun 10, 2004||Nov 11, 2004||Ryota Ohashi||Pump unit|
|US20040237490||Apr 12, 2004||Dec 2, 2004||Toshifumi Yasuda||Power-dividing device and axle-driving device for a working vehicle|
|US20050016304||Apr 26, 2004||Jan 27, 2005||Norihiro Ishii||Vehicle transmission|
|EP1473173A2||Apr 30, 2004||Nov 3, 2004||C.M.C. S.p.a.||Envelope filling machine|
|JP2000009023A||Title not available|
|JP2001146951A||Title not available|
|JP2001263259A||Title not available|
|WO1999067532A1||Jun 22, 1999||Dec 29, 1999||Brueninghaus Hydromatik Gmbh||Dual pump unit|
|1||Dixie Choper, Operation Manual 1998, Cover Page and pp. 50-51, 60-61, 66 Revision #5 Feb. 1998.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7520346 *||Oct 20, 2006||Apr 21, 2009||Parker-Hannifin Corporation||Hydraulic power unit|
|US7726126||Jul 20, 2007||Jun 1, 2010||Hydro-Gear Limited Partnership||Dual pump apparatus with power take off|
|US7900447||Aug 1, 2008||Mar 8, 2011||Hydro-Gear Limited Partnership||Zero turn drive apparatus|
|US8215109||Jul 10, 2012||Hydro-Gear Limited Partnership||Dual pump apparatus with power take off|
|US8327639||Mar 4, 2011||Dec 11, 2012||Hydro-Gear Limited Partnership||Zero turn drive apparatus|
|US8443598||May 21, 2013||Hydro-Gear Limited Partnership||Zero turn drive apparatus|
|US8635867||Jul 15, 2005||Jan 28, 2014||Parker-Hannifin Corporation||Hydrostatic transmission|
|US8707692||May 20, 2013||Apr 29, 2014||Hydro-Gear Limited Partnership||Two piece center section for a drive apparatus|
|US8857171||Feb 11, 2011||Oct 14, 2014||Parker-Hannifin Corporation||Integrated hydrostatic transmission|
|US9010105||May 4, 2012||Apr 21, 2015||Hydro-Gear Limited Partnership||Transmission and engine configuration|
|US9050880||Apr 28, 2014||Jun 9, 2015||Hydro-Gear Limited Partnership||Zero turn drive apparatus and vehicle|
|US9221336 *||Jun 6, 2013||Dec 29, 2015||Hydro-Gear Limited Partnership||Integral power distribution assembly for engine|
|US20070102223 *||Oct 20, 2006||May 10, 2007||Tate Jeremy J||Hydraulic power unit|
|US20110192158 *||Aug 11, 2011||Matthew Herman Simon||Integrated hydrostatic transmission|
|U.S. Classification||60/484, 60/486, 60/487|
|International Classification||B60K17/10, F04B23/06, F04B1/20, F04B23/08, F04B1/32|
|Cooperative Classification||F04B27/02, F04B23/06, F04B23/00, F04B1/324, F04B1/24, F04B1/148, B60K17/105, B60K8/00|
|European Classification||F04B23/06, F04B1/32C|
|Apr 29, 2005||AS||Assignment|
Owner name: HYDRO-GEAR LIMITED PARTNERSHIP, ILLINOIS
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HAUSER, RAYMOND;HOLDER, LONNIE E.;REEL/FRAME:016520/0536
Effective date: 20050429
|Sep 23, 2011||FPAY||Fee payment|
Year of fee payment: 4
|Dec 22, 2015||FPAY||Fee payment|
Year of fee payment: 8